1. Field of the Invention
The present invention relates to a power plug, and more particularly to a pivotable and receivable power plug implemented with a simplified structure and minimum parts.
2. Description of the Related Art
An industrial society heavily and increasingly relies on the use of electric appliances. For the sake of diversified electric appliances in the market and power conversion devices specifically equipped for the electric appliances, a wide range of power conversion devices, such as power extension cords, transformers and rectifiers, are brought into play in that regard. As the power conversion devices must be connected with power sockets of power sources, each power conversion device needs to have a power plug to plug in a corresponding power socket. Usually, the power plugs of the power conversion devices are stationary and are uneasy to be receivable for being bulky.
With reference to FIG. 12, a conventional power converter having a pivotable and receivable power plug that is presented to solve the above issue has a housing 50, a plug 60, a turning piece 53, a positioning piece 54 and a circuit board 70.
The housing 50 has an upper case 51 and a lower case 52 mounted together. The upper case 51 has an elongated opening 511 formed through the upper case 51. The lower case 52 has a first slot 521, a second slot 522 and a third slot 523 to correspond to the elongated opening 511.
The plug 60 is mounted in the first slot of the lower case 52, and has a body 61, two parallel prongs 62, a first pivot shaft 63 and a second pivot shaft 64. The two prongs 62 are formed on a front portion of the body 61. The first pivot shaft 63 and the second pivot shaft 64 are respectively formed on and protrude from two opposite sides of a rear portion of the body 61. The first pivot shaft 63 has an engagement rib 631 formed on and protruding from a cylindrical periphery of the first pivot shaft 63. The second pivot shaft 64 has an angular stop 641 and two parallel conducting elements 621. The angular stop 641 is formed on and protrudes outwardly from a free end of the second pivot shaft 64. The two conducting elements 621 are mounted in one side of the second pivot shaft 64 and are respectively connected to the prongs 62.
The turning piece 53 is mounted in the second slot 522 of the lower case 52, protrudes beyond the elongated opening 511 of the upper case 51, is semicircular and has a semicircular hole 531, an engagement slot 532 and multiple teeth 533. The semicircular hole 531 is centrally formed through the turning piece 53 and mounted around the first pivot shaft 63. The engagement slot 532 is formed in and recessed from an inner wall of the semicircular hole 531 to communicate with the semicircular hole 531 and engage the engagement rib 631. The teeth 533 are formed on and protrude from a semi-circumference of the turning piece 63.
The positioning piece 54 is mounted in the third slot 523 of the lower case 52, and has a pivot hole 541 formed through the positioning piece 54 for the angular stop 641 of the second pivot shaft 64 to be mounted in.
The circuit board 70 is mounted between the upper case 51 and the lower case 52, and has two conducting strips 71 mounted under the circuit board 70 and respectively located at two pivoting paths of the two conducting elements 621.
When the power conversion device is operated, the teeth 533 on the turning piece 53 in the elongated opening 511 of the upper case 51 are turned so that the prongs 62 on the front portion of the body 61 of the plug 60 are pivoted toward the elongated opening 511 and are exposed through the elongated opening 511. When the parallel conducting elements 621 are turned to a specific angle, the angular stop 641 on the second pivot shaft 64 is held by the positioning piece 54 so that the plug 60 is fixed and unrotatable. Meanwhile, the conducting elements 621 on the rear portion of the plug 60 respectively contact the conducting strips 71 and are electrically and respectively connected with the prongs 62 through the conducting strips 71. When the plug 60 is received, the turning piece 53 is turned reversely so that the prongs 62 are pivoted to return to the first slot 521 for storage.
Although the plug 60 of the power conversion device is pivotable and receivable, the conducting elements 621, the first pivot shaft 63 and the second pivot shaft 64 need to be formed on the plug 60 together with the conducting strips 71 and the positioning pieces 54 to ensure that the prongs 62 can be electrically connected with the conducting elements 621 when pivoted. Such structure requiring the use of many parts is not only complicated in manufacture but also expensive in cost.